The purpose of this project is to examine the relationships between nonstandard work among mothers and children's behavior, cognitive test scores, and body mass index (BMI;or weight-for height). We focus on atypical and unpredictable aspects of maternal work that may affect families and children through their impact on income, maternal psychological stress, parenting behavior, family routines, and children's care settings and time use. Our particular focus is on the timing (evenings, weekends or nights) and regularity (work hours that are unpredictable and change from day to day or week to week) of maternal work hours. Specifically, our study has the following goals: Specific Aim 1: Estimate the associations between the timing and regularity of mothers'employment and children's behavior, cognitive test scores, and BMI. Specific Aim 1a: If linkages exist, examine for which of the child development outcomes are such maternal employment conditions the most germane. Specific Aim 1b: If linkages between the timing and regularity of maternal employment and child development are found, examine whether they can be explained by [family income], maternal psychological stress, parenting behavior, family routines, and children's care settings and time use. Specific Aim 1c: Examine whether any of these associations vary by [maternal education, maternal welfare use], race/ethnicity, and children's age, sex, and household structure. Specific Aim 2: In dual-earner households, examine joint associations between mothers'and fathers'work schedules and child development. To answer these questions, we will use data from two data sets, each of which is longitudinal, contains key measures of non-standard work conditions, and is rich with measures of child development and family processes. The work experiences of mothers are clearly of interest, not only to researchers and policy makers, but also to practitioners and others who work directly with families. Our proposed research is unique in its ability to identify the consequences for children of commonly-occurring, but understudied labor market conditions. PUBLIC HEALTH RELEVANCE: The results of this study will identify the consequences for children of common work conditions faced by mothers. This research promises to be significant and relevant for the NIH because the results will identify children who may be at developmental risk due to their parents'employment challenges, as well as children who are faring well. Such findings can not only assist policymakers and practitioners in better understanding the consequences for children of maternal employment, but also point to areas in which new policies and supports are needed in order to promote children's healthy development.